[TIKA-2357] Allow Tesseract PSM up to 13

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.14
• Fix Version/s: 1.15
• Component/s: ocr
• External issue URL: https://github.com/apache/tika/pull/177
• Assignee: Dave Meikle
• Reporter: Dave Meikle
• Created: 08/May/17 12:54
• Updated: 13/Aug/18 18:07
• Resolved: 08/May/17 15:20

Description

From https://github.com/apache/tika/pull/177 by Rafael Ferreira

Extend support for increased PSM options up to 13 for modern versions of Tesseract.

$ tesseract --version
tesseract 3.05.00
 leptonica-1.74.1
  libjpeg 8d : libpng 1.6.29 : libtiff 4.0.7 : zlib 1.2.8

$ tesseract --help-psm
Page segmentation modes:
  0    Orientation and script detection (OSD) only.
  1    Automatic page segmentation with OSD.
  2    Automatic page segmentation, but no OSD, or OCR.
  3    Fully automatic page segmentation, but no OSD. (Default)
  4    Assume a single column of text of variable sizes.
  5    Assume a single uniform block of vertically aligned text.
  6    Assume a single uniform block of text.
  7    Treat the image as a single text line.
  8    Treat the image as a single word.
  9    Treat the image as a single word in a circle.
 10    Treat the image as a single character.
 11    Sparse text. Find as much text as possible in no particular order.
 12    Sparse text with OSD.
 13    Raw line. Treat the image as a single text line, bypassing hacks that are Tesseract-specific.

Issue Links

• is related to: TIKA-2696 Support output of Tesseract OSD output for psm mode 0